Tue, 23 Jan 2024 21:34:12 +0100
bring first scene graph to live
1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
3 * Copyright 2023 Mike Becker. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 *
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
16 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
19 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
20 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
21 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
22 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
23 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
24 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
25 * POSSIBILITY OF SUCH DAMAGE.
26 */
28 #include "ascension/window.h"
29 #include "ascension/context.h"
30 #include "ascension/error.h"
31 #include "ascension/utils.h"
33 #include <cx/printf.h>
35 #include <GL/glew.h>
37 static void asc_gl_debug_callback(
38 GLenum source, GLenum type, GLuint id, GLenum severity,
39 GLsizei length, const GLchar* message,
40 const void* userParam
41 ) {
42 cxmutstr buf = cx_asprintf(
43 "source = %d, id = %u, type = %d, severity= %d, message = %.*s",
44 source, id, type, severity, length, message);
45 if (type == GL_DEBUG_TYPE_ERROR) {
46 asc_error(buf.ptr);
47 } else {
48 asc_dprintf("GL debug: %.*s", (int)buf.length, buf.ptr);
49 }
50 cx_strfree(&buf);
51 }
53 void asc_window_settings_init_defaults(AscWindowSettings* settings) {
54 settings->depth_size = 24;
55 settings->vsync = 1;
56 settings->dimensions.width = 800;
57 settings->dimensions.height = 600;
58 settings->fullscreen = 0;
59 settings->gl_major_version = 4;
60 settings->gl_minor_version = 0;
61 settings->title = "Ascended Window";
62 }
64 static void asc_window_init_scenes(AscWindow *window) {
65 asc_scene_init(&window->ui);
66 }
68 AscWindow *asc_window_initialize(unsigned int index, AscWindowSettings const *settings) {
69 if (index >= ASC_MAX_WINDOWS) {
70 asc_error("Maximum number of windows exceeded.");
71 return NULL;
72 }
73 AscWindow *window = &asc_context.windows[index];
74 if (window->id > 0) {
75 asc_error("Cannot create window - slot already occupied.");
76 asc_dprintf("Tried to create window with index %u", index);
77 return NULL;
78 }
80 Uint32 flags = SDL_WINDOW_OPENGL | SDL_WINDOW_SHOWN;
81 flags |= settings->fullscreen ? SDL_WINDOW_FULLSCREEN_DESKTOP : SDL_WINDOW_RESIZABLE;
83 window->window = SDL_CreateWindow(
84 settings->title,
85 SDL_WINDOWPOS_CENTERED,
86 SDL_WINDOWPOS_CENTERED,
87 settings->dimensions.width,
88 settings->dimensions.height,
89 flags
90 );
91 if (window->window == NULL) {
92 asc_error(SDL_GetError());
93 return NULL;
94 }
96 window->id = SDL_GetWindowID(window->window);
97 SDL_GetWindowSize(window->window,
98 &window->dimensions.width,
99 &window->dimensions.height
100 );
101 asc_mat4f_ortho(
102 window->projection,
103 0,
104 (float) window->dimensions.width,
105 (float) window->dimensions.height,
106 0
107 );
109 SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE);
110 SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, settings->gl_major_version);
111 SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, settings->gl_minor_version);
112 SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, settings->depth_size);
113 SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
114 window->glctx = SDL_GL_CreateContext(window->window);
115 if (window->glctx == NULL) {
116 asc_dprintf("Creating GL context failed for window %u", window->id);
117 } else {
118 glewExperimental = GL_TRUE;
119 GLenum err = glewInit();
120 if (err == GLEW_OK) {
121 SDL_GL_SetSwapInterval(settings->vsync);
122 glEnable(GL_DEPTH_TEST);
123 glEnable(GL_BLEND);
124 glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
125 glEnable(GL_DEBUG_OUTPUT);
126 glDebugMessageCallback(asc_gl_debug_callback, NULL);
128 asc_dprintf("Window %u initialized", window->id);
129 if (asc_primitives_init(&window->primitives)) {
130 asc_window_init_scenes(window);
131 asc_context.active_window = window;
132 return window;
133 } else {
134 asc_dprintf("!!! Creating primitives for window %u failed !!!", window->id);
135 }
136 } else {
137 asc_error(glewGetErrorString(err));
138 }
139 }
141 // cleanup on error
142 if (window->glctx != NULL) {
143 SDL_GL_DeleteContext(window->glctx);
144 }
145 window->glctx = NULL;
146 SDL_DestroyWindow(window->window);
147 window->window = NULL;
148 window->id = 0;
149 }
151 void asc_window_destroy(AscWindow* window) {
152 // safeguard
153 if (window->id == 0) return;
155 // this window cannot be active anymore
156 if (asc_context.active_window == window) {
157 asc_context.active_window = NULL;
158 }
160 // destroy all scenes
161 asc_scene_destroy(&window->ui);
163 // release context related data (we have to make the GL context current for this)
164 SDL_GL_MakeCurrent(window->window, window->glctx);
165 asc_primitives_destroy(&window->primitives);
167 // destroy the GL context and the window
168 if (window->glctx != NULL) {
169 SDL_GL_DeleteContext(window->glctx);
170 }
171 if (window->window != NULL) {
172 SDL_DestroyWindow(window->window);
173 }
175 // if another window was active, make the other context current again
176 if (asc_context.active_window != NULL) {
177 AscWindow const *aw = asc_context.active_window;
178 SDL_GL_MakeCurrent(aw->window, aw->glctx);
179 }
181 // clean the data
182 asc_dprintf("Window %u and its OpenGL context destroyed.", window->id);
183 memset(window, 0, sizeof(AscWindow));
184 }
186 void asc_window_sync(AscWindow const* window) {
187 AscWindow const *active_window = asc_context.active_window;
188 if (window != active_window) {
189 asc_window_activate(window);
190 }
192 // Clear viewport for new frame
193 glViewport(0, 0, window->dimensions.width, window->dimensions.height);
194 glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
195 glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
197 // Draw the UI
198 asc_scene_draw(&window->ui);
200 // Swap Buffers
201 SDL_GL_SwapWindow(window->window);
203 if (window != active_window) {
204 asc_window_activate(active_window);
205 }
206 }
208 void asc_window_activate(AscWindow const *window) {
209 SDL_GL_MakeCurrent(window->window, window->glctx);
210 asc_context.active_window = window;
211 }